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    <ul>
        <li>
            <h3>数组的扁平化</h3>
            <ol>
                <li>
                    <h4>使用递归的方式进行扁平化的处理</h4>
                    <img src="/img/knowledge/bian1.png" alt="">
                </li>
                <li>
                    <h4>使用reduce方法简化递归操作</h4>
                    <img src="/img/knowledge/bian2.png" alt="">
                </li>
                <li>
                    <h4>使用最简单的方法 toString方法</h4>
                    <img src="/img/knowledge/bian2.png" alt="">
                </li>
            </ol>
        </li>
    </ul>
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